Intermittent projector movement



2 Sheets-Sheet 1 PEG. 4

lllllluirlgllllq ra I,

R. SMID INTERMITTENT PROJECTOR MOVEMENT V ATTORNEYS.

Original Filed Oct R. SMID INTERMITTENT PROJECTOR MOVEMENT OriginalFiled Oct. 28, 1946 Feb. 21, 1950 2 Sheets-Sheet 2 FIIG. 9

3 & 3 6 3 3 4 s y n 7/|.% mH: F1.| Ill I w r? v I;

FHGH

FHG. B0

A inn;

INVENTOR RUDQ PH SMID ATTORNEYS.

Patented Feb. 21, 1950 UNITED STATES PATENT OFFICE Substituted forapplication Serial No. 706,199, October 28, 194.6. This applicationApril 9, 1948,

Serial No. 19,921

. Claims. 1

My invention relates to film controls for motion picture projectors, andmore particularly to mechanisms which impart the intermittent feedingmovement to the film, and one object is to provide a mechanism whichfeeds the film smoothly and without injuring the same.

This application is a substitute, for abandoned application, SerialNumber 706,199, filed October 28, 1946.

A further object is to combine a positive film advancing element with acoacting element which gently se arates the film from the feed at thestops or intervals between the advancing movements of the. film.

Another object is to provide spring means effective to hold the film inits normal path While the feed periodically releases the same.

An important object is to provide a rotary control for the filmlfeedwhich is positive and quiet in operation.

With the above objects in view, and any others which may suggestthemselves from the description to follow, a better understanding of theinvention may be had by reference to the accompanying drawings, in WhichFig. 1 is a side elevation of the mechanism as enclosed in a case andfilm guide;

Fig. 2 is a section on the line 22 of Fig. 1;

Figs. 3 and 4 are, respectively, sections on the lines .,-3 and 44 ofFig.2;

Fig. 5 is a section on the line 5-5 of Fig. 3;

Fig. 6 is a section on the line 66 of Fig. 1;

Fig. 7 is an elevation of a fragment of the film;

Fig. 8 is an enlarged duplication of the film feed control in Fig. 3,with dotted lines showing a change of position;

Figs. 9 to 11 are views similar to Fig. 8 and illustrating othercharacteristics of the control; and

Fig. 12 is an enlargement of the right-hand portion of Fig. 6, showingthe film feed more clearly.

Referring specifically to the drawings, denotes the base plate of theimproved mechanism. the same being vertically positioned and extendedfrom its outer side with a tubular bearing 2| for a drive shaft 22. Theparts ofthe mechanism are almost entirely located on the inner side ofthe plate 20 and enclosed by a case 23 having a back. wall and top andbottom walls 25.

The shaft 22 is designed for rotation from the power element of theprojector, the direction in which the shaft is rotated being immaterial.

The shaft is partly journaled in the bearing 2!, and passes through thecase 23 to be additionally journaled in a bearing 21 carried by thesame. The film 23 controlled by the mechanism is of the conventionalvariety indicated in Fig. '7 and having a row of perforations 29 alongone edge.

The cycle of the film feed is to engage. the film, draw it through adownstroke, disengage the film, and take an upstroke free of the same.For this purpose the mechanism contains a unit to impartthe downstrokeand upstroke and a second unit to' procure the disengaging and engagingoperation, both units being actuated in harmonious sequence by therotation'of the shaft 22.

For the operation of the downstroke and upstroke of the film feed, amechanism carried by the plate it" is employed. Accordingly, the platehas a pair of upper and lower brackets 30 on the inner side, thesehaving laterally spaced arms 3!. Each vertical pair of arms carries arod 32'; and therods form ways for cars 34 at the corner of a carriage35 to render the carriage slidable along the rods, or in a verticaldirection. The

carriage is formed with a pair of angle plates.

3 5 whose flanges 3! occur in opposed relation. The plates 35 areapplied to the carriage by means of screws 38 passed through elongatedslots 39 in the plates. Thus, these may be adjusted toward and away fromeach other to fix the position of the flanges 31.

The shaft 22 carries a cam 4|] between the fiangesx l of the angleplates 36. The cam has uniformly climbing edges 41 between short andlong part-circular portions 42 and 43. Thus, these portions serve asdwells in respect to the flanges 31, while the edges 4| serve toalternately raise and lower the carriage 35 as the shaft is rotated ineither direction.

The carriage 35 has a frontal block 48 in which a rod 59 is insertedwith one end from the front and retained in the block by a set screw 50.The other end of the rod 49 is inserted in the shanlctl of a verticalplate 52 such shank receiving a set screw 53 to fix the shank on therod. The plate 52 is designed to form a backing guide for the film 28,and it is understood that such guide is made to be removable from thecar-,- riage by means of the set screw and adjustable relative to thesame by means of the set screw 53. So far as described, the mechanismhas no ef- Ifecton the fim, only providing a guide along the back sidethereof.

" The means for periodically advancing the film and releasing the sameat'the end of each adthe headlpiece.

Vance will now be described. It is noted that the carriage 35 has a pairof vertically spaced bearings 55 at the rear and another pair ofsimilarly spaced bearings 56 in the center. These bearings serve for theslidable disposal of a pair of horizontal rods 58. These are spanned bya pair of vertical bars 59 through the end portions of which the rodspass, such end portions being secured to the rods by screws 60. The bars59 are designed to serve as followers on opposite sides of a cam 52carried by the drive shaft 22. As in the previous case, the cam 62 has apair of climbing edge portions 53 between part-circular dwell portions64 and 65, although the climb of the present cam is much less than thatof the cam 40. It is now understood that the screws 50 serve to spacethe bars 59 for a proper relation with the edge of the cam 62.

The horizontal rods 58 are forwardly extended to slidably receive across-head l9, and further extended to receive sleeves H. The rodsterminate as screws to receive nuts 13 formed with nicked heads M.Compression springs I occur between the heads it and the cross-head 10.

The film guide may be of any conventional form, having a front wall 80,a side wall 8| and a rear wall 82. The latter has an opening 89 intowhich the plate 52 freely extends, such plate being substantially in theplane of the rear wall 82.

The film 23 is designed to move along the frontal face of such wall, andis urged thereagainst by the feet 85 of an arched :presser plate 86. Thesaid feet receive screws 88 from the front of the wall 89; and springs90 are coiled around the screws between the wall 80 and the presserplate feet 85 to yieldably engage the presser plate with the film.

The cross-head I9 is extended forwardly with a short medial stem 9| towhich a lateral bend 92 of a headpiece 93 is secured by screws 94. Theheadpiece occurs directly in front of the plate 52 and travels up anddown with the same because the plate is rigidly attached to the carriageand the headpiece receives its vertical support from the latter. On theother hand, the headpiece is free to move horizontally in forwarddirection to recede from the plate 52 as well as in rearward directionto approach the same, this motion being controlled by the rotation ofthe cam 62 in relation to the follower bars 59.

The rear face of the headpiece 93 has a medial horizontal groove 99opening at the free end of Near such end a stud 91 projects rearwardlyfrom the fioor of the groove. Thus,

when the headpiece is close to the film 28, the

stud has advanced through a given perforation 29 thereof into aregistering perforation 52a made in the plate 52, so that when theheadpiece and the plate descend together, the stud draws the filmthrough a downstroke. The free end of the stud is rounded to facilitateits entrance into the film perforation 29.

The groove 96 receives in its closed end one end .of a leaf spring 99,such leaf spring end being secured to the headpiece by a rivet I90.

headpiece closes on the film as indicated by full lines in the samefigure. However, when the headpiece and plate 52 reach the lower end ofthe downstroke, the cam 62 acts to move the headpiece in the forwarddirection. This action operates to withdraw the stud 91 from the plateand film perforations 52 and 29. However, in case the film has atendency to cling to and move with the stud, the automatic relaxation ofthe spring 99 (from the full-line to the dotted-line position of Fig. 12will insure the separation of the film from the stud, whereby to freethe film from the head piece before the latter assumes its upwardstroke. The headpiece and the plate 52 thus rise with the headpiece awayfrom the film while the latter is stationary. When the headpiece hasreached the upper end of its stroke the stud 9'! will arrive at a heighteven with the next upper film perforation 29, so that the closing of theheadpiece on the film by the action of the cam 62 will project the studthrough the said perforation and again secure a positive hold on thefilm.

Ordinarily, the cross-head l0 and the headpiece 93 move as one with thefollower bars 59, this presupposing that the film is passing smoothlythrough the guide. However, where the film contains a splice, theheadpiece must yield to allow the thicker portion of the film sulficientclearance, and it does this by drawing on the cross-head 19 against thesprings 15. This feature also permits the advance of the headpiece whenthe film is to be threaded through the device between the headpiece andthe plate 52.

It is now apparent that the novel mechanism has several meritoriousfeatures. First, it mounts the driving cam along the single shaft 22 andfixes the position of the latter in the bearings of the base plate andthe case of the mechanism. Further, the carriage is compactly groupedaround the shaft and includes both the vertical and horizontal controlsfor the movement of the film. Further, the film guide springs may bedesigned to exert the proper pressure on the film to permit its uniformpassage without undue friction. Further, the film feed includes both apositive propelling element for the film and an automatic device torelease the same the moment the propelling element recedes from thefilm. Further, with the case walls 25 forming end limits for the rods32, the latter may be made slidable in the bracket arms 3| and thereforeremovable therefrom to permit the entire working mechanism to be takenout from between the brackets and by way of the film guide opening 83for repair, adjustment or other alteration. Finally, the novel mechanismis a compactly designed unit which can be conveniently installed inprojectors of the conventional type.

While I have described the invention along specific lines, various minorchanges or refinements may be made therein without departing from itsprinciple, and I reserve the right to employ all such changes andrefinements as may come within the scope and spirit of the appendedclaims.

I claim:

1. An intermittent projector movement comprising a film guide, a baseplate, bearing means carried by the same, a carriage slidable in saidbearing means in a path parallel to the course of film travel, anextension on said carriage at right angle to said bearing means forminga backing for the film, a unit transversely slidable in the carriage andprovided with a headpiece positioned in front of the film and inhorizontal alignment with said extension, means for producing areciprocatory sliding movement on the part of the carriage and a liketransverse movement on the part of said unit in a manner to move saidextension and headpiece in unison along the course of the film and toperiodically advance said headpiece toward the path of the film, meanscarried by the headpiece to positively engage the film on such advance,and other means releasing said film on the retracting movement of theheadpiece.

2. The structure of claim 1, the means carried by the headpiece being astud adapted to enter the conventional traction perforation of the film.

3. The structure of claim 1, said means for releasing the film being aspring adapted to engage the frontal side of the film.

4. The structure of claim 1, said means for releasing the film being aspring adapted to engage the frontal side of the film, such spring beingcarried by the headpiece.

5. The structure of claim 1, said means for releasing the film being aSpring adapted to engage the frontal side of the film, such spring beingcarried by the headpiece and tensioned to bear rearwardly on the film.

6. The structure of claim 1, said means for releasing the film being aspring adapted to engage the frontal side of the film, such spring beingcarried by the headpiece and tensioned to bear rearwardly on the film,the means carried by the headpiece being a stud, and said spring havinga perforation for the passage of the stud on the retracting movement ofthe headpiece.

7. The structure of claim 1, said means for releasing the film being aspring adapted to engage the frontal side of the film, such spring beingcarried by the headpiece and tensioned to bear rearwardly on the film,the means carried by the headpiece being a stud, said spring having aperforation for the passage of the stud on the retracting movement ofthe headpiece, and the latter having a groove opposite the spring andadapted to receive the same in such event.

8. The structure of claim 1, the headpiece being separate from the unit,and yieldable means holding the headpiece in engagement with the unit,such yieldable means being effective to permit the separation of theheadpiece from said extension in the event of the passage of a splice orotherwise thickened film portion therebetween.

9. An intermittent projector movement comprising a film guide, a baseplate, bearing means carried by said base plate, said means comprisingupper and lower spaced brackets having laterally spaced arms, verticallydisposed rods journalled in said arms for joining said brackets, acarriage slidable on said rods in a path parallel to the course of filmtravel, means on said carriage and at right angles to said rods forminga backing for the film, a unit transversely slidable in the carriage andformed with a head piece positioned in front of the film, means forproducing a reciprocatory sliding movement on the part of the carriageand a like transverse movement on the part of said unit in a manner tomove said film backing means and head piece in unison along the courseof the film and to periodically advance said head piece toward the pathof the film, means carried by the head piece to positively engage thefilm on such advance, and other means releasing said film on theretracting movement of the head piece.

10. An intermittent projector movement comprising a film guide, a baseplate, bearing means carried by said base plate, said means comprisingupper and lower spaced brackets having laterally spaced arms, verticallydisposed rods journalled in said arms for joining said brackets, acarriage slidable on said rods in a path parallel to the course of filmtravel, means on said carriage and at right angles to said rods forminga backing for the film, a unit transversely slidable in the carriage andformed with a head piece positioned in front of the film, said headpiece being united with said film backing means in a manner to movevertically therewith or to move horizontally in a forward or rearwarddirection independently of said backing means, means for producing areciprocatory sliding movement on the part of the carriage and a liketransverse movement on the part of said unit in a manner to move saidfilm backing means and head piece in unison along the course of the filmand to periodically advance said head piece toward the path of the film,means carried by the head piece to positively engage the film on suchadvance, and other means releasing said film on the retracting movementof the head piece.

RUDOLPH SMID.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,305,002 Oiler May 27, 19191,403,339 Mitchell Jan. 10, 1922 2,037,972 Gillet Apr. 21, 19362,174,579 Grifiin et al. Oct. 3, 1939 FOREIGN PATENTS Number CountryDate 103,511 Great Britain Jan. 26, 1917

